<span>The heliocentric model of the
universe was proposed by Nicolaus Copernicus. There are numerous scientist in
ancient times who try to explain what happens in the universe. He may not be
the first one who proposed that what astronomical body is the center of the
universe. However, he stated that the center of the universe was the sun, not
the earth. And the earth revolves around it. It is in his book on the
Revolutions of the Heavenly Bodies. It was only published as he lay in his
deathbed. </span>
A. A stretched catapult can do work when released so it must have potential energy.
b. A stone on the ground will not move on its own ever again so it has zero energy.
c. In order to roll an object there must be a friction force between the object and the ground (otherwise it will slide)
d. To lift a stone you must overcome the weight which is the force due to gravity.
e. Work and energy are both measured in Joules.
We know that
• The mass of the elevator is 5000 kg.
Let's draw a free-body diagram.
As you can observe, there are just two forces involved, the weight of the elevator and the tension force. Let's use Newton's Second Law.
But, W = mg = 5000kg*9.8m/s^2 = 49,000 N, and m = 5000 kg, a = 0 (because the speed is constant).
<h2>Therefore, the tension in the cable is 49,000 N.</h2>
Answer:
young's modulus
Explanation:
We have given length of tendon L= 13 cm =0.13 m
Change in length 
Force = 12.1 N
Average diameter d =8.8 mm
So 
Area 
Now stress 
Strain 
Now young's modulus
